[Python-Dev] peps: document requirements

Christian Heimes christian at python.org
Mon Sep 30 21:31:10 CEST 2013

Am 30.09.2013 20:16, schrieb Antoine Pitrou:
> On Mon, 30 Sep 2013 17:08:00 +0200 (CEST)
> christian.heimes <python-checkins at python.org> wrote:
>> +
>> +* It should return ``0`` for zero length input. (Note: This can be handled as
>> +  special case, too.)
> What is this required for? The main requirement is that equal stuff
> hashes equal, but there's no reason for zero-length input to hash to
> zero, AFAIK.


    We make the hash of the empty string be 0, rather than using
    (prefix ^ suffix), since this slightly obfuscates the hash secret

It's not a hard requirement, hence 'should' instead of 'must' like in
all other cases.


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